Journal article

Publication year: 2020

Journal: Energy, Sustainability and Society

Volume number: 10

Issue number: 1

ISSN: 2192-0567

Open access status: Gold

DOI Link: https://doi.org/10.1186/s13705-020-00258-1

Publisher: BioMed Central

Abstract: 
Background Rushes are prominent wetland plants that are well adapted to conditions of waterlogging. Tall rushes like soft rush (Juncus effususL.) tend to dominate the vegetation and offer a great biomass potential. Removing rush biomass is often necessary to enhance various ecosystem services of wetlands. There is an urgent need for sustainable use of the removed biomass apart from expensive composting ore useless landfill. Methods We investigated three alternative energy utilisation routes for soft rush biomass and evaluated their energetic potential: biomethanisation via wet fermentation technique (a), biomethanisation via solid-state fermentation technique (b) and combustion (c). Batch experiments (a), experimental fermenters (b), and thermo-calorimetric equipment (c) were used to measure energy output per unit rush biomass input. Results The wet fermentation technique had significantly higher biogas yields than solid-state fermentation (399 L(N)kg(-1)oDM compared to 258 L(N)kg(-1)oDM). These yields constitute 59 and 43%, respectively, of the biogas potential of maize silage as a reference. Solid-state fermentation technique needs longer retention time compared to wet co-digestion to earn comparable methane yields. Soft rush biomass shows high heating values (15.06 MJ kg FMw15-1) compared to other herbaceous solid fuels. Conclusions Low costs for substrate production make energetic utilisation ofJuncus effususan interesting alternative, if short distances between fields and biomass conversion plant can be realised. All investigated conversion routes appear promising, provided that the substrate specifics are considered in the design of the conversion technique. Besides the size of the rush dominated area and the distribution of these areas in the landscape, the investment costs and the subsidies for the conversion plant play a pivotal role in the selection of the preferred conversion path.

Harvard Citation style: Mueller, J., Jantzen, C. and Wiedow, D. (2020) The energy potential of soft rush (Juncus effususL.) in different conversion routes, Energy, Sustainability and Society, 10(1), Article 26. https://doi.org/10.1186/s13705-020-00258-1

APA Citation style: Mueller, J., Jantzen, C., & Wiedow, D. (2020). The energy potential of soft rush (Juncus effususL.) in different conversion routes. Energy, Sustainability and Society. 10(1), Article 26. https://doi.org/10.1186/s13705-020-00258-1